While riding the bike, oil used to get on the spark plug, causing the engine to turn off, and the mileage had dropped to 36/37. Therefore, upon the advice of an expert technician, a new carburetor was purchased and installed. Even after that, when the problem was not solved, another mechanic was consulted, and he said the problem was not with the carburetor, but with the spark plug (this situation happened because the expert mechanic treated the problem as a complex case from the beginning!). And after changing the spark plug, the problem was indeed resolved. The new carburetor cannot just be thrown away, so I kept it installed. Now I am willing to sell the original carburetor that came with the bike.